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Gallimimus
Gallimimus was a fast, ostirich-like dinosaur that lived in what is now Mongolia during the Late Cretaceous period. Information Gallimimus was found in the Gobi Desert in Mongolia in early 1963 by Professor Zofia Kielan-Jaworowska. It was named by palaeontologist Richen Barsbold in 1972, who thought it looked rather rooster-like in appearance. Most fossils have been found in Mongolia. At this time only one species of Gallimimus is known, and it is named Gallimimus bullatus, because of the bulbous swelling in the brain-case resembled a bulla; a capsule which was worn by Roman youths around their necks. The cervical vertebrae of Gallimimus indicate that it held its neck obliquely, declining upwards at an angle of 35 degrees. Osmólska and colleagues found that the hands of Gallimimus were not prehensile (or capable of grasping), and that the thumb was not opposable. They also suggested that the arms were weak compared to, for example, those of the ornithomimosaur Deinocheirus. They agreed with the interpretations of ornithomimid biology by palaeontologist Dale Russell from earlier in 1972, including that they would have been very fleet (or cursorial) animals, although less agile than large, modern ground birds, and would have used their speed to escape predators. Russell also suggested that they had a good sense of vision and intelligence comparable to that of modern ratite birds. Since their predators may have had colour vision, he suggested it would have influenced their colouration, perhaps resulting in camouflage. In 1982, palaeontologist Richard A. Thulborn estimated that Gallimimus could have run at speeds of 42-56 km/h. He found that ornithimimids would not have been as fast as ostriches, which can reach 70-80 km/h, in part due to their arms and tails increasing their weight. In 1988, Paul suggested that the eyeballs of ornithomimids were flattened and had minimal mobility within the sockets, necessitating movement of the head to view objects. Since their eyes faced more sideways than in some other bird-like theropods, their binocular vision would have been more limited, which is an adaptation in some animals that improves their ability to see predators behind them. Paul considered the relatively short tails, which reduced weight, and missing halluxes of ornithomimids to be adaptations for speed. He suggested that they could have defended themselves by pecking and kicking, but would have mainly relied on their speed for escape. In 2015, Akinobu Watanabe and colleagues found that together with Deinocheirus and Archaeornithomimus, Gallimimus had the most pneumatised skeleton among ornithomimosaurs. Pneumatisation is thought to be advantageous for flight in modern birds, but its function in non-avian dinosaurs is not known with certainty. It has been proposed that pneumatisation was used to reduce the mass of large bones, that it was related to high metabolism, balance during locomotion, or used for thermoregulation. In 2017, Lee and colleagues suggested various possible taphonomic circumstances (changes during decay and fossilisation) to explain how the Gallimimus foot discovered in 2009 was associated with a trackway. The trackway is preserved in sandstone while the foot is preserved in mudstone, extending 20 centimeters below the layer with the tracks. It is possible the fossil represents an animal that died in its tracks, but the depth of the foot in the mud may be too shallow for it to have become mired. It may also have been killed by a flood, after which it was buried in a pond. However, the layers of mud and sand do not indicate flooding but probably a dry environment, and the disrupted sediments around the fossil indicate the animal was alive when it came to the area. The authors thus suggested that the tracks had been made over an extended amount of time and period of drying, and that probably none of them were produced by the individual that owned the foot. The animal may have walked across the floor of a pond, breaking through the sediment layer with the tracks while it was soaked from rain or contained water. The animal may have died in this position from thirst, hunger, or another reason, and mud then deposited on the sand, thereby covering and preserving the tracks and the carcass. The foot may have become clenched and disarticulated as it decomposed, which made the tendons flex, and was later stepped on by heavy dinosaurs. The area may have been a single bone bed (based on the possible number of poached specimens) representing a Gallimimus mass mortality, perhaps due to a drought or famine. The fact that the animals seem to have died at the same time (the empty excavation pits were stratigraphically identical) may indicate that Gallimimus was gregarious (lived in groups), which has also been suggested for other ornithomimids. Osmólska and colleagues pointed out that the front part of the neck of Gallimimus would have been very mobile (the hind part was more rigid), the neural arches in the vertebrae of that region being similar to chicken and other Galliformes, indicating similar feeding habits. They found the beak of Gallimimus similar to that of a duck or goose, and that it would have fed on small, living prey which it swallowed whole. The mobility of the neck would have been useful in locating prey on the ground, since the eyes were positioned on the sides of the skull. They assumed that all ornithomimids had similar feeding habits, and pointed out that Russel had compared the beaks of ornithomimids with those of insectivorous birds. Osmólska and colleagues suggested that Gallimimus was capable of cranial kinesis (due to the seemingly loose connection between some of the bones at the back of the skull), a feature which allows individual bones of the skull to move in relation to each other. They also proposed that it did not use its short handed forelimbs for bringing food to the mouth, but for raking or digging in the ground to access food. The hands of Gallimimus may have been weaker than for example those of Struthiomimus, which may instead have used its hands for hooking and gripping, according to a 1985 article by palaeontologists Elizabeth L. Nicholls and Anthony P. Russell. In 1988 Paul disagreed that ornithomimids were omnivores that ate small animals and eggs as well as plants, as had previously been suggested. He pointed out that ostriches and emus are mainly grazers and browsers, and that the skulls of ornithomimids were most similar to those of the extinct moas, which were strong enough to bite off twigs, as evidenced by their gut content. He further suggested that ornithomimids were well adapted for browsing on tough plants and would have used their hands to bring branches within reach of their jaws. Palaeontologist Jørn Hurum suggested in 2001 that due to its similar jaw structure, Gallimimus may have had an opportunistic, omnivorous diet like seagulls. He also observed that the tight intramandibular joint would prevent any movement between the front and rear portions of the lower jaw. In 2001, palaeontologists Mark A. Norell, Makovicky, and Currie reported a Gallimimus skull (IGM 100/1133) and an Ornithomimus skull that preserved soft tissue structures on the beak. The inner side of the Gallimimus beak had columnar structures that the authors found similar to the lamellae in the beaks of anseriform birds, which use these for manipulating food, straining sediments, filter-feeding by segregating food items from other material, and for cutting plants while grazing. They found the Northern shoveller, which feeds on plants, molluscs, ostracods, and foraminiferans, to be the modern anseriform with structures most similar in anatomy to those of Gallimimus. The authors noted that ornithomimids probably did not use their beaks to prey on large animals and were abundant in mesic environments, while rarer in more arid environments, suggesting that they may have depended on aquatic food sources. If this interpretation is correct, Gallimimus would have been one of the largest known terrestrial filter feeders. In 2005, palaeontologist Paul Barrett pointed out that the lamella-like structures of Gallimimus did not appear to have been flexible bristles like those of filter-feeding birds (as there is no indication of these structures overlapping or being collapsed), but were instead more akin to the thin, regularly spaced vertical ridges in the beaks of turtles and hadrosaurid dinosaurs. In these animals, such ridges are thought to be associated with herbivorous diets, used to crop tough vegetation. Barrett suggested that the ridges in the beak of Gallimimus represented a natural cast of the internal surface of the beak, indicating that the animal was a herbivore that fed on material high in fibre. The discovery of many gastroliths (gizzard stones) in some ornithomimids indicate the presence of a gastric mill, and therefore point towards a herbivorous diet, as these are used to grind food of animals that lack the necessary chewing apparatus. Barrett also calculated that a 440 kilogram Gallimimus would have needed between 0.07 and 3.34 kilograms of food per day, depending on whether it had an endothermic or an ectothermic ("warm" or "cold"-blooded) metabolism, an intake which he found to be unfeasible if it was a filter feeder. He also found that ornithomimids were abundant not only in formations that represented mesic environments, but also in arid environments where there would be insufficient water to sustain a diet based on filter feeding. In 2007, palaeontologist Espen M. Knutsen wrote that the beak shape of ornithomimids, when compared to those of modern birds, was consistent with omnivory or high-fibre herbivory. In-Game Gallimimus will be in the early access of Prehistoric Kingdom. Gallery GalliAlt.png|Old, now scrapped, design Gallimimus 01 Preview.png|Allium Gallimimus 02 Preview.png|Silver Spalding Gallimimus 03 Preview.png|Rose Thorn BAcGXA9.jpg Wn44cRM.jpg|All the skins Category:Dinosaurs Category:Omnivore Category:Theropod